Thune thinks he'll be more effective in solving the country's problems of debt and spending in the Senate rather than running for president the next two years. It's a decision that may have been the toughest one he's faced yet.

"I've been back and forth on this. There are days when I've been really committed to proceeding and moving forward, and then there are days when I say this isn't something I really see myself doing right now. Part of that comes back just to the tie I feel, the sense of responsibility, and obligation, and duty to my job in the Senate," Thune said.

"Around the holidays that started to change and I think part of it too was gaining the recognition and realization that it would be really hard to do two jobs at the same time," Thune said.

Thune was concerned about juggling his duties in the Senate while running for president.

"The thing that's probably troubled me the most as I've sort of weighed this and worked through it is the idea that I'd have to give up my day job. In other words, that I wouldn't be able to devote the time and resources and energy that I think I need to do my job in the Senate, and to representing South Dakota there," Thune said.

The long and costly campaign for the Republican nomination, and then a face-off with President Barack Obama also weighed on his mind. Earlier this month Thune and his wife, Kimberley, talked about the rigors of expensive hard-fought campaigns and the toll it takes on a family.

"The amount of resources it takes to do this anymore is so overwhelming. I mean President Obama in his last election raised almost $1 billion. They say he will raise more than one billion this time," Thune said during a February 5th interview.

"The campaign is intense. It's very intense and I take it personally. He would let things roll off and I would take it personally," Kimberley Thune said during an interview with KELOLAND News on February 5th.

Even though Thune points out that his family was supportive no matter what he wanted to do, he says those same concerns that he had a few weeks ago are the same concerns he has now.

"We've been through tough campaigns before but it's usually a year. My wife always kind of looks at things, okay I can do this for this amount of time, but there's an end line out there. In this case, if things went well you'd get to the year and then you'd have another year to go, both of which would be long, hard campaigns. So, obviously that weighs on you," Thune said Tuesday.

Those who are closest to Thune think not running for president is the right call. Former South Dakota Senator Jim Abdnor is his political role model. Thune even worked for Abdnor when he started his career.

"That's a big job running for president. You got to be in 50 states to try and pick up help and that doesn't come easy," Abdnor said.

Abdnor doesn't think Thune had the recognition nationally to make a solid run at the White House, but he does think highly of Thune and thinks some day he will run for president.

"He really isn't that well known. He will be. This guy has talent and capability coming out of his ears and I think highly of him," Abdnor said.

Now, Thune will focus on his job in the Senate and continue to direct the policies of the Republicans as the fourth-ranking member of his party. Thune believes that's where he can have the most impact on the issues facing America.

"We're going to be the place where I think some of those big battles are waged over the course of the next couple years. The finance committee, and the budget committee, both committees where I now serve is where a lot of that is going to occur," Thune said.

And that's why Thune thought it was best to stay the course in the Senate instead of jumping into the race for the top job in Washington.

"I just came to the conclusion, at least for now, I'm where I'm supposed to be. We're going to work as hard as we can, and I'm going to be the best Senator I possibly can be."

As for which Republican he supports in 2012, Thune says since no one has officially said they are running he isn't supporting anyone right now.

Below is the interview Ben Dunsmoor had with Thune shortly after the announcement.

That also goes for the rumors that he could be a potential vice presidential candidate in 2012. Until the Republican nomination is made Thune says that would be pure speculation right now.